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Hi,<br>
<br>
I'm writing a patch for ghcmod-vim so that a user can look up the
haddock html documentation for a symbol. My code makes three system
calls, e.g. to look up "Just" it does:<br>
<br>
$ ghc-mod info foo.hs Foo Just<br>
data Maybe a = ... | Just a -- Defined in `Data.Maybe'<br>
<br>
$ ghc-pkg find-module Data.Maybe --simple-output<br>
haskell2010-1.1.1.0 base-4.6.0.1<br>
<br>
$ ghc-pkg field base-4.6.0.1 haddock-html<br>
haddock-html:
/home/carlo/opt/ghc-7.6.3_build/share/doc/ghc/html/libraries/base-4.6.0.1<br>
<br>
Then "Data.Maybe" is changed to Data-Maybe.html" and appended to the
haddock-html value. But this procedure doesn't work in general, for
example when looking up String:<br>
<br>
$ ghc-mod info foo.hs Foo String<br>
type String = [Char] -- Defined in `GHC.Base'<br>
<br>
$ ghc-pkg find-module GHC.Base<br>
/home/carlo/opt/ghc-7.6.3_build/lib/ghc-7.6.3/package.conf.d<br>
base-4.6.0.1<br>
/home/carlo/.ghc/x86_64-linux-7.6.3/package.conf.d<br>
<br>
$ ghc-pkg field base-4.6.0.1 haddock-html<br>
haddock-html:
/home/carlo/opt/ghc-7.6.3_build/share/doc/ghc/html/libraries/base-4.6.0.1<br>
<br>
$ ls
/home/carlo/opt/ghc-7.6.3_build/share/doc/ghc/html/libraries/base-4.6.0.1/GHC-Base.html<br>
ls: cannot access
/home/carlo/opt/ghc-7.6.3_build/share/doc/ghc/html/libraries/base-4.6.0.1/GHC-Base.html:
No such file or directory<br>
<br>
because the html is in the src subdirectory:<br>
<br>
$ ls
/home/carlo/opt/ghc-7.6.3_build/share/doc/ghc/html/libraries/base-4.6.0.1/src/GHC-Base.html<br>
/home/carlo/opt/ghc-7.6.3_build/share/doc/ghc/html/libraries/base-4.6.0.1/src/GHC-Base.html<br>
<br>
But this isn't even the right place to go, one should look at the
Prelude file<br>
<br>
<a
href="http://hackage.haskell.org/package/base-4.6.0.1/docs/Prelude.html#t:String">http://hackage.haskell.org/package/base-4.6.0.1/docs/Prelude.html#t:String</a><br>
<br>
which is what Hoogle suggests. How does Hoogle get it right?<br>
<br>
It looks like haskell-mode for emacs runs into a similar problem:<br>
<br>
<meta http-equiv="content-type" content="text/html;
charset=ISO-8859-1">
<a
href="https://github.com/haskell/haskell-mode/blob/master/inf-haskell.el#L734-L740">https://github.com/haskell/haskell-mode/blob/master/inf-haskell.el#L734-L740</a><br>
<br>
-------------------------------<br>
(defvar inferior-haskell-ghc-internal-ident-alist<br>
;; FIXME: Fill this table, ideally semi-automatically.<br>
'(("GHC.Base.return" . "Control.Monad.return")<br>
("GHC.List" . "Data.List")))<br>
<br>
(defun inferior-haskell-map-internal-ghc-ident (ident)<br>
"Try to translate some internal GHC identifier to its alter ego
in haskell docs."<br>
-------------------------------<br>
<br>
Thanks,<br>
<br>
<pre class="moz-signature" cols="72">--
Carlo Hamalainen
<a class="moz-txt-link-freetext" href="http://carlo-hamalainen.net">http://carlo-hamalainen.net</a></pre>
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